I think Saitama is stronger. His power is seemingly limitless and he has never struggled in a fight. Goku, although powerful, has had many intense battles where he was pushed to his limits.
One interesting storyline could be that Goku, being the ever - eager fighter, challenges Saitama not knowing the true extent of his power. Saitama, on the other hand, is just looking for a normal grocery shopping day. The clash of their personalities, Goku's excitement and Saitama's nonchalance, could lead to a very comical start. Then as the fight progresses, they both start to respect each other's power in different ways.
In a one - on - one fight between One Punch Man (Saitama) and Goku, it's really tough to say. Saitama is known for being able to defeat any opponent with just one punch. However, Goku has a vast array of powerful forms and techniques. If Saitama landed his first punch, he'd win instantly. But Goku's speed and ability to constantly power up could potentially give him an edge. He could keep dodging Saitama's punches until he found a way to overpower him. It really depends on how the fight is set up in the fanfiction.
One interesting plot point is the clash of power systems. Goku's ki - based attacks and transformations like Super Saiyan contrast sharply with Saitama's pure physical strength. For example, in some fanfictions, when they first meet, there's a sense of mutual curiosity about each other's power sources.
Another interesting piece of fanfiction is one that delves into a tournament - style story. Goku, being the battle - hungry Saiyan he is, enters a tournament in the One Punch Man world. Here, he meets all kinds of unique fighters. The fanfiction does a great job of exploring how Goku's fighting style and abilities interact with the different power - scaling and rules of the One Punch Man universe. It's a really engaging read for fans of both series.
It depends on personal preferences. Some people might think the manga is better because it has more detail and original ideas. But others might prefer the anime for its animation and voice acting.
In fanfiction, it's possible for Naruto to be stronger than Goku. Fanfic writers often tweak the power levels and rules of the characters' universes. For example, if the fanfic writer decides to nerf Goku's Saiyan abilities while enhancing Naruto's Sage Mode and all his ninja skills to an extreme level, Naruto could end up being stronger.